Automatic yarn piecing apparatus for ring spinning frame or the like



Nov. 17, .1970

ZENZABURO TSUKUMO ETAI- AUTOMATIC YARN PIECING APPARATUS FOR RING SPINNING FRAME OR THE LIKE 16 Sheets-Sheet l Filed Feb. 20, 1968 l l Il Il Il 'e Il l l1 ll El cr l NGV- 17, 1970 zENzABuRo TsUKuMo ETAL AUTOMATIC YARN PIECING APPARATUS FOR RING SPINNING FRAME OR THE LIKE Flled Feb 20, 1968 16 Sheets-Sheet 2 INVENT OR ATTORNEY NOV. 17, 1970 zENzABURo TSUKUMO ETAL 3,540,200

I AUTOMATIC YARN PIECING APPARATUS FOR RING SPINNING FRAME OR THE LIKE Filed Feb. 20, 1968 16 Sheets-Sheet 3 Q E i NOV- 17, 1970 zENzABuRo TsuKuMo ETAL AUTOMATIC YARN PIECING APPARATUS FOR RING SPINNING FRAME OR THE LIKE Flled Feb 20, 1968 16 Sheets-Sheet 4 NOV- 17, 1970 zENzABURo rsuKuMo ETAL 3,540,200

' AUTOMATIC YARN PIECING APPARATUS FOR RING SPINNING FRAME OR THE LIKE Filed Feb. 2o. 1968 16 sheets-sheet 5 Nov. 17, 1970 zENzABuRo TsUKUMo ETAL 3,540,200

AUTOMATIC YARN PIECING APPARATUS FOR RING SPINNING FRAME OR THE LIKE Filed Feb. 20,' 1968 1S Sheets-Sheet 6 NOV. 17, 1970 ZENZABURO TSUKUMQ ETAL 3,540,200

AUTOMATIC YARN PIECING APPARATUS FOR RING SPINNING FRAME 0R THE LIKE Flled Feb 2O 1968 16 Sheets-Sheet 7 Nov. 17, 1970 zENzABuRo TsuKUMo ETAL 3,540,200

AUTOMATIC YARN PIECING APPARATUS FOR RING SPINNING FRAME OR THE LIKE Flled Feb 20, 1968 16 Sheets-Sheet 8 NOV. 17, 1970 ZENZABURO TSUKUMO ETAL 3,540,200

AUTOMATIC YARN PIECING APPARATUS FOR RING SPINNING FRAME 0R THE LIKE Filed Feb. 20. 1968 i lGSheets-Sheet 9 I Le; 1..,4.

Nov. 17, 1970 ZENZABURO TSUKUMO ET AL AUTOMATIC YARN PIECING APPARATUS FOR RING SPINNING FRAME OR THE LIKE Filed Feb. 20, 1968 16 Sheets-Sheet lO NOV 17, 1970 zENzABURo TsuKUMo ET AL` 3,540,200

AUTOMATIC YARN PIECING APPARATUS FOR RING SPINNING FRAME OR THE LIKE Filed Feb. 20, 1968 16 Sheets-Sheet l1 NOV. 17, 1970 ZENZABURO TSUKUMQ ETAL 3,540,200

AUTOMATIC YARN PIECING APPARATUS FOR RING SPINNING FRAME OR THE LIKE Filed Feb. 20, 1968 16 Sheets-Sheet I2 Nov. 17, 1970 zENzABURo AUTOMATIC PIECI YARN UKuM-o ETAL 3,540,200

APPARATUS FOR RING SPINNING FRAME OR THE LIKE Filed Feb.` 20, 1968 16 Sheets-Sheet 15 NOV. 17, 1970 ZENZABURO TSUKUMO ETAL 3,540,200

AUTOMATIC YARN PIECING APPARATUS FOR RING SPINNING FRAME 0R THE LIKE Filed Feb. 20. 1968 16 Sheets-Sheet 14.

l g i! |98 :g /lj/ l S NOV. 17, 1970 ZENZABUROVTSUKUMO ETAL 3,540,200

AUTOMATIC YARN PIECING APPARATUS FOR RING SPINNING FRAME 0R THE LIKE Filed Feb. 20. 1968 16 Sheets-Sheet 15 19| ZOO 201 Hg. /QA

NOV. 17, 1970 ZENZABURO TSUKUMO ETAL 3,540,200

AUTOMATIC YARN PIECING APPARATUS FOR RING SPINNING FRAME 0R THE LIKE Filed Feb. 20, 1968 16 Sheets-Sheet 16 United States Patent 3,540,200 AUTOMATIC YARN PIECING APPARATUS FOR RING SPINNING FRAME R THE LIKE Zeuzaburo Tsukurno, Nishinomiya-shi, Takeki Sato, Takarazuka-shi, Kanehiro Ito, Amagun, Aichi-ken, and Noboru Ohashi, Akashi-shi, Japan, assignors to Toyo Boseki Kabushiki Kaisha, Osaka, Japan, and Howa Kogyo Kabushiki Kaisha, Aichi-keu, Japan, both companies of Japan Filed Feb. 20, 1968, Ser. No. 706,876 Claims priority, application Japan, Aug. 17, 1967, 42./53,061 Int. Cl. D01h 15/00 U.S. Cl. 57-34 12 Claims ABSTRACT 0F THE DISCLOSURE An automatic yarn piecing apparatus is provided with a detector for sensing a yarn breakage during winding of a supply yarn around a winding bobbin and a yarn piecing mechanism. The yarn piecing mechanism carries a supplementary yarn supply cop and when a yarn breakage is detected, one end of the supplementary yarn is wound around the winding bobbin at which the breakage occurred. The yarn piecing mechanism includes means for then parting the supplementary yarn into two sections, each having a jagged end, and means for pressing together one of the jagged ends with a portion of the original supply yarn which was broken to effectively join the supplementary yarn with the supply yarn.

The present invention relates to an improved apparatus for automatically piecing broken yarns on spinning machines.

The conventional yarn piecing apparatus developed up to now can be classified into two types, that is, one is an apparatus characterized by means for extracting the broken end of yarn from -a bobbin and means for piecing the extracted yarn directly with a drafted roving or sliver issuing from the producing roller of the corresponding spinning unit of the ring spinning frame, while the other is an apparatus characterized by a piecing mechanism comprising means for taking a supplementary yarn from a supply cop supported 'by the apparatus when an absence of one of the threads moving to-ward bobbins supported by the spindles of a ring spinning frame is detected and means for winding the supplementary yarn taken from the supply cop about a bobbin whose yarn is broken and means for cutting a yarn connection between the supplementary yarn and piecing the end portion of the supplementary yarn and the bobbin with a eece delivered from a producing roller of a corresponding spinning unit just after threading the supplementary yarn wound about the bobbin through a traveller riding on a ring of the spinning unit.

Although many improvements on the above-mentioned apparatus have been introduced, it is said that these apparatus are not available vfor our practical purpose at the present situation.

The principal object of the present invention is to provide an improved automatic yarn piecing apparatus having many practical characters, such as easy operative functions without any troubles.

The other object of the present invention is to provide a compact yarn piecing apparatus t for all types of spinning mills without reinstallation of the spinning frames.

ICC

Other objects and features of the invention will more fully appear from the following description and the accompanying drawings and will be particularly pointed out in the claims.

FIG. 1 is a back side view of an automatic yarn piecing apparatus according to the invention,

FIGS. 2A and 2B are left and right hand side views respectively of the apparatus shown in FIG. 1,

FIG. 3 is a perspective view showing the front side of the apparatus shown in FIG. 1,

FIG. 4 is a block diagram showing the function of a detector for detecting the absence of spinning yarn, according to the invention,

FIG. 5 illustrates various waveforms of elements of the detector shown in FIG. 4,

FIG. 6A is a perspective view of a detector according to the invention,

FIG. 6B is a plan view of a mechanism to provide a swinging motion of the detector shown in FIG. 5,

FIGS. 7 and 8 are a perspective view of mechanism for stopping the apparatus at its correct working position according to the invention, and anelevation of a portion of the mechanism, respectively,

FIG. 9 is a skeleton sketch, showing the main portion of the apparatus shown in FIG. 1,

FIG. 10A is a perspective view of a braking mechanism for controlling a rotating speed of a spindle of a ring spinning frame, according to the invention,

FIG. 10B is a perspective view of another embodiment of the braking mechanism of the apparatus according t0 the invention,

FIG. 11 is a sectional side view of a nipper of the yarn piecing apparatus of the invention,

FIG. 12A is a skeleton sketch, showing mainly the mechanism for reserving the supplementary yarn disposed in the apparatus shown in FIG. 1. FIG. 12B is a skeleton sketch of another embodiment of the mechanism for reserving the supply yarn according to the invention,

FIG. 13 is a perspective View of a winding mechanism for winding a supplementary yarn about a bobbin which is supported by a spindle of a ring spinning frame, according to the invention,

FIG. 14 is a plan view of the Winding mechanism shown in FIG. 13,

FIG. 15 is an elevational view, partly in section of a guide member of the supplementary yarn, which is one of the elements of the -winding mechanism shown in FIG. 13,

FIG. 16 is an explanatory drawing showing the relative positions of the winding mechanism shown in FIG. 13 and a ring with a traveller of a spinning unit,

FIGS. 17A, 17B, 17C, 17D, 17E and 17F are plan views showing the operation of the winding mechanism shown in FIG. 13,

FIGS. 18A and 18B are a side and plan views of an embodiment of yarn piecing mechanism according to the invention,

FIG. 18C is an enlarged plan View of a portion of the yarn piecing mechanism partly in section, shown in FIG. 18B,

FIGS. 19A, 19B, 19C and 19D are side views showing the operation of the yarn piecing mechanism according to the invention,

FIG. 20 is a programming diagram showing the rela tive relation of the time function with respect to the camprole of programming cams for controlling the motion of the members of the automatic yarn piecing apparatus shown in FIG. 1,

FIG. 21 is a skeleton sketch, side elevation of the apparatus showing the main portion thereof, according to the invention.

GENERAL MECHANISM OF YARN PIECING APPARATUS OF THE INVENTION AND ITS OPERATION The apparatus of the invention is characterized by a novel means for piecing yarn or strands of fibers with the drafted roving or sliver issuing from the producing roller where the yarn i-s broken and the breakage of the yarn is detected. The novel means for piecing yarn with the drafted roving or sliver according to the invention can be applied to both of the above-mentioned types of automatic yarn piecing apparatus. The apparatus of the invention is further characterized by means for threading yarn through a traveller.

One of the typical embodiments of the automatic yarn piecing machine according to the invention, which is applied to the latter type is hereinafter illustrated.

A typical apparatus according to the invention comprises a carriage adapted Vfor moving in front of and along spindles of one or more ring spinning frames; a detector for detecting absence of spinning yarns of the respective spinning units of ring spinning frames; means for stopping the carriage at a correct working position of the apparatus when the detector detects a yarn breakage; means for reserving a supplementary yarn supplied from a supply cop supported by lthe apparatus, winding mechanism for winding the reserved supplementary yarn around a bobbin supported by a spindle wherein a spinning yarn is broken; means for threading the supplementary yarn through a traveller riding on a ring of the spindle after completion of winding the supplementary yarn around the bobbin; means for piecing one end of a parted supplementary yarn which is connected to the bobbin with a fleece issuing from a pair of front rollers of the spinning unit wherein the spinning yarn is broken just after parting the supplementary yarn between the supply cop and a nipper which grips the end portion of the reserved supplementary yarn connected to the bobbin; and a programming cam mechism .for regulating motions of the above-mentioned members of the apparatus.

Referring to FIGS. 1, 2A, 2B 3 and 4, an embodiment of the automatic yarn piecing apparatus according to the invention is encased in a carriage 1 provided with a pair of front wheels 2 and a pair of drive wheels 3 which drives the carriage 1 when the apparatus is carried outside of the operative position of ring spinning frames, for example, the carriage 1 is carried from a ring spinning frame to the adjacent ring spinning frame by means of the operation of the drive wheels 3. The drive wheels 3 are driven by a suitable means such as an electric motor 4 and its power transmission mechanism. As shown in the drawing, a drive wheel 8 and guide wheel 7 are disposed to the carriage 1 so that these wheels are engaged with a guide rail 6 secured to the ring spinnig frame S during the working operation of the apparatus 1 for guiding it along the spindle rail of the ring spinning frame 5. Other well-known driving mechanisms, such as a trolley system may be applied for carrying the apparatus.

The automatic yarn piecing apparatus is carried along the guide rail 6 of the ring spinning frame 5 and, when a detector 10 detects a yarn breakage, the detector 10 actuates the electric circuit of the motor 4 so as to stop the motor 4 and a brake 57 disposed on the carriage 1 is actuated by the output of the detector 10 so that the brake 57 comes in contact with a brake rail 59 which is disposed adjacent to the spinning frame 5 in a parallel condition with the guide rail 6, thereby the carriage 1 is carried only by its inertia and then stops. Just after the brake 57 has been applied, means for correcting the working position of the carriage 1 engages with one of the setting pins 11 secured to the spinning frame 5 with an equal interval corresponding to a spindle gauge of the frame 5, thereby the carriage 1 is stopped at the correct working position. The abovementioned interval between the pins 11 may be chosen as a multiple of the space of the spindle distance. Next, a nipper 23 gripping a leading end portion of yarn reserved by a supplementary yarn reserve mechanism 22 (FIG. 3) is carried downward along a vertical shifting guide 21 by a motion of a shifting mechanism provided with a chain 24 of the shifting mechanism while a mechanism 25 for leading and guiding the end portion of the supply yarn (hereinafter referred to as a winding mechanism) is carried downward along a vertically shifting guide 21 by means of a guiding motion of a chain 27 of the shifting mechanism as shown in FIG. 3. The winding mechanism 25 stops its downward motion when it contacts with a ring rail 17 of the spinning frame 5. And the nipper 23 also stops its downward motion when it contacts with a stopper Secured to the mechanism 25. These positions wherein the nipper 23 and the winding mechanism 25 are stopped are at positions which are hereinafter referred to as the operating positions, respectively. While the nipper 23 and the winding mechanism 25 are being carried downwards, a spindle braking mechanism 28 stops the rotation of the spindle or decreases the rotation speed of the spindle by its braking action to against a spindle braking pulley 14 secured under a spindle wharve 15 of the spindle wherein the yarn is broken. The nipper 23 and the winding mechanism 25 are always pulled downwards by a spring or counter balance (not shown) and are supported by the respective carrying members secured to the chains 24, 27 of the respective shifting mechanism so as to restrict the free movement in the downward direction. When the nipper 23 and the winding mechanism 25 arrive at their operative positions and are stopped by the above-mentioned mechanism, the leading end portion of the supplementary yarn is transferred from the nipper 23 to a supporting member of the winding mechanism 25, then a friction pulley of the spindle braking mechanism 28 is positively driven at a low speed for controlling the spindle speed while ejecting the end portion of yarn, which is supported by the supporting member of the winding mechanism 25, by jet air stream blown in the tangential direction of a ring from a nozzle disposed to the carriage 1, whereby the end portion of the supply yarn is wound around a cop 12 supported by the spindle, and just after the-winding motion of the supplementary yarn around the cop 12, a traveller 18 is slid on the ring `16 by the action of jet air blown from the other nozzle disposed to the carriage 1, next the traveller 18 is stopped at a predetermined position by a stopper disposed to the winding mechanism 25. When a yarn guide member of the winding mechanism 25 leads the supplementary yarn extending from the nipper 23 to the cop 12 so that the supplementary yarn contacts with the flange of the ring 16, the traveller is ridden on the yarn guide member by the action of jet air blow, thereby the supplementary yarn is threaded through the space between the ring 16 and the traveller. Next, the nipper 23 is carried upwards along the vertical shifting guide 21 while permitting the free passing of the supplementary yarn, and returns to its original position. While the nipper 23 is being carried upwards, a tail end portion of the supplementary yarn is positioned at the operative position of a yarn piecing mechanism 29. Next the yarn piecing mechanism 29 leads the tail end portion of the supplementary yarn to an approach position to the nip point of the front rollers of the spinning unit of the spinning frame 5 and then the tail end portion of the supplementary yarn is parted by a parting means of the yarn piece in mechanism 29 in such a way that the tail end portion of the supplementary yarn is transferred to the yarn piecing mechanism 29 so as to grip the tail end portion of the supplementary yarn ternporarily. When a parted portion of the supplementary yarn connected to the cop is carried to the bottom front roller and contacted with a fleece issuing from the front rollers by means of the yarn piecing mechanism, the parted portion of the supplementary yarn is pieced with the fleece. Thereafter the yarn piecing mechanism 29 recedes from the operative position and returns to its original position, while the winding mechanism 25 is also carried upwards and returned to its original position. When the supplementary between the nipper 23 and the yarn piecing mechanism 29 is parted, the nipper 23 grips firmly the supplementary yarn which is supplied from the supply cop through the supplementary yarn reserve mechanism 22. Consequently, when the next piecing motion of the apparatus starts, a leading end portion of the supplementary yarn is projected from the nipper 23. Further the spindle is released from the engagement with the spindle braking mechanism 28 at a time just before the completion of the yarn piecing motion of the apparatus. The above-mentioned yarn piecing operation is carried out without troubles in other words carried out satisfactorily. Then the detector works again to confirm the completion of the yarn piecing motion of the apparatus. Next, the apparatus is carried along the guide rail 6 until the detector 10 detects an occurrence of a broken yarn. It is also possible to operate the detector 10 in such a way that the miss operations of the above-mentioned yarn piecing operation of the apparatus, the apparatus is operated again or the trouble is informed by a suitable device such as an alarm so as to call the attention of the operator.

Generally, it is well known that a large number of flies are stuck to machine parts of the spinning frame.

Consequently, in case the detection of a reflection from a spinning yarn of a spinnig unit is applied for detecting a yarn breakage, it is quite possible to detect a reflection from a fly, thereby perfect detection by the detector is disturbed very much.

According to the present invention, a novel method for detecting the absence of the spinning yarn is applied t o prevent the above-mentioned miss-detection, that is, vibration of a spinning yarn passing through a yarn passage between a nip point of front rollers and a snail wire of a spinning unit is particularly considered'and a modified detecting method by sensing a reflection in a wave form is applied to distinguish spinning yarn in a normal spinning condition from a yarn breakage.

Referring to FIGS. 3, 4, 5, 6A and 6B, an embodiment of the detector 10 of the invention comprises a projector 31, a light receiver 32 for receiving a reflected light from a yarn, an element of a photo-electric transducer (not shown) which transforms the output ofthe receiver 32 into an electric output, a filter and amplifier 35 which detects only a component signal of the element of the photo-electric transducer having a predetermined frequency, a shaper 36 for shaping the output of the iilter and amplifier 35, a counter 37 for counting the pulse of the shaper 36, a detecting head 40 for detecting a position of corresponding spindle 13, another shaper 41 for shaping the output of the detecting head 40 into a signal of a square wave form, an off delay timer 42 to make an output signal which is maintained longer for a predetermined period than the duration of the square wave output of the shaper 41, a .memory 38 for keeping the output signal of the counter 37 while the output signal of the off delay timer `42 is maintained, a gate circuit 39 to which the output of the shaper 41 and memory 38 and off delay timer 42 are put in, and a relay 43 'which is actuated by the output of the gate circuit r9` and actuates the yarn piecing mechanism of the apparatus. Further, a swing mechanism for swinging the projector 31 together with the light receiver 32 is provided. The operative character of the detector 10 is illustrated by the drawings of FIGS.

4 and 5. When the detecting head 40 detects the existence of the spindle, the output signal f is given and the signal g is provided by the off delay timer 42 at the same time. Ori the other hand, in case there is no yarn breakage, the light from the projector 31 is reiiected by the spinning yarn of the normal spinning condition, and the reflected light caused by the spinning yarn in a vibration form is detected by the receiver 32 so that the reflected light received by the receiver 32` is in a compound form with some reflected lights from several parts of the ring spinning frame oi` flies. Then the reflected light received by the receiver 32 is changed into an electric signal a. by the element of the photo-electric transducer. It is considered that the output signal a is composed of signal x corresponding to a reflection from a spinning yarn passing through a passage between the front rollers and a snail wire 20 of a spinning unit and the other signal y corresponding to a reflection from several parts of the spinning frame or files. Therefore, it is necessary to only detect the signal x by an action of the filter and amplifier 35, The output signal b corresponding to the signal x can be obtained by the filter and amplifier 35. The output signal b is further changed to a corresponding pulse signal c by the shaper 36, and the pulse signal c is counted as a signal d by the counter 37. In case the signal d becomes a predetermined value, a pulse signal e is obtained and the pulse signal e is memorized by the memory 38 during the duration of a signal g of the off delay timer 42. This signal is represented by h. As mentioned above, the disturbance caused by the reflection of some flies, can be eliminated. On the contrary, in case the pulse signal e is not obtained, in other words, in case the spinning yarn is broken, no signal is memorized by the memory 38. In FIG. 5, the abscissa of all diagrams represent time, while the ordinates represent the magnitude of the respective signals. In the diagram of a signal h of the memory 38, a portion designated by P shows the signal h when the spinning of the yarn is operating without troubles, while a portion designated by Q shows the signal h when a yarn breakage is detected. As already illustrated, the signals f, g and h are put into the gate circuit 39. And the output signal of the gate circuit 39 is 'finally detected by the balancing condition between the signals g and h, that is, the output signal i of the gate circuit 39 does not exist in case the signal l1 is at the condition of P, while the signal z' exists at the condition of Q of the signal h. When the signal i exists, a pulse signal R is obtained, therefore, when the pulse signal R is obtained in other words, when a spinning yarn is broken, the relay 43 is excited by the signal R.

Even if the yarn piecing operation of the apparatus has been operated after detecting a yarn breakage, it is not certain whether the yarn piecing operation has been performed completely or not, consequently, the confirmation of the operation may preferably be required for practical use of the yarn piecing apparatus in the mill. For the above-mentioned purpose, means for confirmation of the piecing yarn operation may be added to this embodiment of the invention. Referring to FIGS. 6A and 6B, the projector 31 and the receiver 32 are secured to the saine bracket 33 with an angle such that the projector B1 illuminates the spinning yarn between the front rollers and the snail wire 20, while the receiver 31 receives the reflected light from the yarn. The bracket 33 is secured to a vertical shaft 45 rotatably supported by a bracket 34 secured to the frame of the yarn piecing apparatus. Further, a horizontal arm 44 is secured to the vertical shaft 45, one end portion of the horizontal arm 44 is connected with the front end portion of a flexible wire l46 which is operated by a programming cam (not shown), another end of the horizontal arm 44 is connected with a helical spring 49 secured at its end to the frame of the yarn piecing apparatus. A guide tube 48 of the flexible wire 46 is supported by a bracket 47 secured to the frame of the apparatus. After completion of the yarn piecing operation,

7 the flexible Ewire 46 is pulled toward the right in FIG. 6B

by an action of the programming cam, consequently, the horizontal arm V44 is turned clockwise while resisting to the force of the spring `49, thereby the projector 31 and the receiver 32 are turned to the position shown by the dotted line so as to face the detecting position of the spinning unit where the piecing operation has just been iinished, thereby, the detecting operation is carried out again on the spinning unit to confirm the completion of the yarn piecing operation.

The position of the projector 31 shown by the solid line shows its normal working position.

The detecting operation mentioned above is carried out on each spinning unit while the yarn piecing apparatus moves along a working front of the ring spinning frame 5. In a modified embodiment of the detector according to the present invention, when a ymiss operation of the abovementioned yarn piecing operation is detected by the confirmation operation which is already described, the miss operation is counted. However, the operation of the apparatus is continued until the counted number of the miss operation becomes a predetermined value and when the counted value becomes the predetermined one, the apparatus is stopped automatically by a suitable means and the trouble is noticed by operators by a suitable means such as an alarm.

MEANS FOR STOPPING THE APPARATUS AT ITS CORRECT WORKING POSITION Referring to FIGS. 2A, 2B, 3, 7 and 8 means for stopping the apparatus at its correct working position (hereinafter referred to as a stop means) firstly brakes the movement of the carriage 1 when a yarn-breakage is dedetected by the detector 10, and an engaging arm 70 is projected forwards simultaneously thereby the carriage 1 is stopped at a position adjacent to its working position, next a correcting device provided with an engaging member 53 is operated in such a way that the engaging member 53` engages with the setting pins 11 so as to stop the carriage 1 at the correct working position of the apparatus.

As shown in FIG. 2, the apparatus is carried along an upper rail 19 disposed to the frame 5 and the brake rail 59 disposed under the upper rail 19, and a plurality of setting pins 11 for correcting the stop position of the carriage 1 are disposed to the upper rail 19 in such a way that the pins 11 are arranged at an equal interval which corresponds to several times greater than a spindle distance. For example, in the embodiment shown in FIG. 8, the pins 11 are arranged at the positions corresponding to alternate spindles. The brake rail 59 works toI support the apparatus. Generally, the upper rail 19 can be attached to the spindle rail of the ring spinning frame or is replaced with the guide rail `6. The engaging member 53 is provided with a plurality of engaging grooves 54 opened upwardly. The lateral space between the adjacent grooves 54 coincides with the spindle distance so as to engage one of the grooves 54 with one pin 11 when the engaging member 53 is shifted upwardly. To obtain easy engagement of the engaging grooves 54 with the pin 11, the top portion of the engaging groove 54 is wider than its lower portion. When the pins 11 are disposed to the upper rail 19 as shown in FIG. 7, the engaging member must be provided with two engaging grooves 54, and if the lateral space between the adjacent pins 11 corresponds to a distance three times larger than the spindle distance, the engaging member 53 must be provided with three engaging grooves 54. The engaging member 53 is maintained at its lowermost position while carrying the carriage 1, and is shifted upwards when the carriage 1 is stopped so as to engage a groove 54 with one of pin 11 for stopping the carriage 1 at the correct working position of the apparatus.

In FIG. 7, a braking device and an embodiment stop means are shown. The braking device comprises an electromagnet 55, a lever l56 and the brake 57. The electromagnet 55 is actuated by an output of the detector 10 8 when the detector 10 detects yarn breakage. A lever 56 is turnably mounted on a shaft 58 and one end of the lever 56 is connected to the electromagnet through a helical spring 60, while the other end forms the brake S7 which rides upon a brake rail 59. Consequently, when the electric magnet 55 is actuated and the end of the lever 56 is pulled upwards, the lever 56 is turned in such a way that the brake 57 contacts with the brake rail 59 strongly so as to brake the motion of the apparatus. Further an electromagnet 61 is actuated simultaneously or just after the actuation of the electromagnet 55. The electromagnet 61 is actuated by a signal from the above mentioned stop means, and turns a shaft 67 through a lever 63 pivoted to a fixed shaft 62 and connecting rods 64 and 65. The shaft 67 is rotatably supported by a pair of cannon Vbrackets 68a, l681i in such a way that the shaft 69 does not move in the lateral direction. To obtain the above-mentioned feature, a stopper 69 is secured to the shaft 67, the engaged portion of the shaft 67 with an engaging arm 70* is provided with the configuration of a spline shaft and a compression spring 71 is mounted on one end portion of the shaft 67 so as to form a shock absorber. A Washer 72 is mounted on the end of the shaft 67. The engaging arm 70 is supported at its receded position in the carriage 1 during the movement of the carriage 1 so as to disengage from pins 11, on the contrary, when the electromagnet 61 is actuated, the top portion of the engaging arm 70 is moved forward and engaged with the pin 11, the electromagnet 55 is also actuated simultaneously so as to break the movement of the apparatus by the action of the brake 57, thereby the carriage 1 is stopped at the engaged position of the engaging arm 70 with the pin 11. However, the abovementioned stopped position of the carriage 1 is not always the correct operating position. In the present embodiment, when the carriage 1 is stopped as mentioned above, the Working elements of the electromagnets 55 and 61 are returned to their waiting position, and the carriage 1 is released from the condition of engagement between the brake 57 and the brake rail 59. Next, the correcting device for correcting the stopped position of the carriage 1 is actuated. In the correcting device a wheel 74 is secured to a shaft of a motor 73, and is meshed with a wheel of a shaft 75. The shaft 75 is supported by cannon brackets 76a, 76b, and cams 77, 79 for operating limit switches 78 and y80 and pinions 81, `82 are secured to the shaft 75. The cams 77, 79 are engaged with the respective limit switches 78 and 80 so as to stop the engaging member 53 at its upper or lower most positions. The motor 73 is actuated by a limit switch (not shown) after stopping the carriage 1, thereby the engaging member 53 moves upwards by the engagement of the rack portions of it with the pinions 81, 82 of the shaft 75. By this upward motion of the engaging member 53, one of the grooves 54 engages with the pin 11, thereby the stop position of the carriage 1 is corrected to the correct operating position. And the engagement of the engaging member 53 with the pin 11 is maintained at the correct operating position of the carriage 1 till the yarn piecing operation is completed. After the completion of the yarn piecing operations, the motor 73 rotates in the reverse direction thereby the engaging member 53 moves downwards so as to release the engagement of the engaglng member 53 with the pin 11, and next the carriage 1 moves again. Instead of using a single motor as described above, a pair of driving motors, which rotate in reverse direction, may be used for shifting the engaging member 53.

SPINDLE SPEED CONTROL MECHANISM Referring to FIGS. 2, 3, 9 and 10A, the rotation of the spindle can be controlled by a positive engagement of the spindle brake pulley 14 secured coaxially to a portion right under a spindle wharve 1S of the respective spindles 13 with a friction pulley 83 of a spindle speed control mechanism 28 for controlling the rotation of the spindle. Consequently the rotation speed of the spindle 13 can 

